"Biochemical Targets of Plant Bioactive Compounds" - stop ecocide & speciescide

The World has entered an Anthropocene Era in which the impact of Man on Nature is causing mass extinction of species. However in addition to aesthetic arguments about respect for irreplaceable complexity, there is a powerful utilitarian argument for preserving natural ecosystems in that they contain a wealth of bioactive plant compounds of potential pharmaceutical utility as documented in my huge 860-page book “Biochemical Targets of Plant Bioactive Compounds” [1].

Kew Royal Botanic Gardens comments thus on the threat to plant diversity: “One of the most challenging questions facing scientists is ’how many species are there in the world?’… Using expert analysis, scientists from Kew generated a more accurate estimate of 352,000 in a paper published in 2008. However, many flowering plant groups have yet to be assessed and the true number is likely to be just over 400,000. New plant species continue to be discovered, too, while others are under threat of extinction… We know that 22% of plant species already face the threat of extinction. Research also tells us that it is the impact of human actions and activity that poses the greatest threat to plant diversity today. A global analysis of extinction risk for the world’s plants conducted by Kew has revealed that the world’s plants are as threatened as mammals, with one in five of the world’s plant species threatened with extinction. In some areas and in certain groups of plants the figure is much higher. For example half of Madagascar’s 188 palm species were discovered by Kew experts in the last 20 years, and 90% of these are threatened with extinction” [2].

The Guardian records the current plant and animal diversity (2010): “As well as the likely 400,000-odd flowering plants, there are thought to be 15,000 species of ferns and their allies, 1,000 gymnosperms such as conifers, and 23,000 mosses and allies making up the plant kingdom. For comparison there are more than 1 million species of insects listed by science, 28,000 living species of fish, 10,000 birds and 5,400 mammals” [3].

Mycologists David Hawksworth and Amy Rossman have commented on fungal diversity (1997): “The hypothesis that there are 1.5 million fungal species on Earth, of which only about 70,000 are described, implies that 1.43 million remain undescribed. The recognition that many new species have yet to be found is of fundamental importance to plant pathologists, agronomists, and plant regulatory officials, among others, who continue to encounter diseases caused by previously unknown or understudied fungi. Unexplored habitats with their arsenal of unknown fungi are also of interest to those searching for novel organisms for use in biological control or for their pharmaceutical attributes. This paper presents data on the expected numbers of fungi in some relatively unexplored habitats, such as tropical forests, and those obligately associated with plants, lichens, and insects” [4]. Plants , animals and fungi are Eukaryotes whereas bacteria are Prokaryotes. Estimates of the number of bacterial species range from 5 million to 1 billion [5].

However burgeoning human population, and neoliberal greed have had a huge impact on Nature. Biologists Dr Phillip Levin and Dr Donald Levin (2002): “The numbers are grim: Some 2,000 species of Pacific Island birds (about 15 percent of the world total) have gone extinct since human colonization. Roughly 20 of the 297 known mussel and clam species and 40 of about 950 fishes have perished in North America in the past century. On average, one extinction happens somewhere on earth every 20 minutes. Ecologists estimate that half of all living bird and mammal species will be gone within 200 or 300 years. Although crude and occasionally controversial, such statistics illustrate the extent of the current upheaval, which spans the globe and affects a broad array of plants and animals… The current losses are, however, exceptional. Rates of extinction appear now to be 100 to 1,000 times greater than background levels, qualifying the present as an era of "mass extinction"” [6].

Civilized people respect beauty and irreplaceable complexity. They are appalled when works of art are stolen, damaged or destroyed. However, while modern technology means that drawings, paintings and even large sculptures are essentially replaceable, the remorseless exigencies of economic growth are destroying things that we cannot reproduce, unique species and the complex ecosystems in which they live. This mass destruction of ecocsystems (ecocide) and species (speciescide) is now compounded by worsening, man-made climate change through industrial and agricultural generation of greenhouse gas (GHGs). Thus, for example, huge forest ecosystems and fisheries are now moving towards the poles. Indeed the international consensus basis of the latest IPCC Summary for Policymakers (2014) has resulted in a report that softens the present acute seriousness of unaddressed man-made climate change. Thus the IPCC Summary argues for a limitation of temperature rise to 2oC through limiting greenhouse gas (GHG) pollution of the atmosphere to 450 ppm CO2-equivalent but hard evidence says that we have already reached 478 ppm CO2 -equivalent, that 2oC is dangerous and essentially inevitable, and that the world will use up its terminal Carbon Budget for a 75% chance of avoiding plus 2oC within about 4 years [7].

Powerful utilitarian, economic arguments have been advanced for the preservation of what remains of wild nature. Thus Dr Andrew Balmford and numerous colleagues (2002): “On the eve of the World Summit on Sustainable Development, it is timely to assess progress over the 10 years since its predecessor in Rio de Janeiro. Loss and degradation of remaining natural habitats has continued largely unabated. However, evidence has been accumulating that such systems generate marked economic benefits, which the available data suggest exceed those obtained from continued habitat conversion. We estimate that the overall benefit:cost ratio of an effective global program for the conservation of remaining wild nature is at least 100:1” [9].

The economic benefits from preserving what remains of wild nature include contentment, recreation, tourism, sustainable economic development, and sustenance of insect pollinators crucial for agriculture. However, as briefly outlined below, a major utilitarian argument for preservation of remaining ecosystems relates to huge potential chemical resources for lead compounds for pharmaceutical development.

Plants contain secondary metabolites that are not involved in the primary plant processes of plant structure, metabolism and reproduction but are elaborated for defence against plant-eating organisms such as animals and fungi (eukaryotes) and bacteria (prokaryotes). Indeed many animals, fungi and bacteria can also generate bioactive secondary metabolites. Many of the plant secondary metabolites are exploited by humans to give taste to food, in herbal medicines, as perfumes, and for psychoactive properties.

The diversity of secondary metabolites expands greatly when they can be covalently modified in vivo by addition of sugars (glycosylation) or other chemical compounds. In the case of bioactive proteins (amino acid polymers or polypeptides) the diversity expands greatly through evolution of different functional sequences, gene duplication within a species and the possibilities of covalent modification in vivo (e.g. by glycosylation, acylation and proteolytic processing).

The total number of unique bioactive secondary metabolites that could be potentially isolated from the circa 3 million eukaryotes (plant, fungi and animals) could be of the order of millions. Of this huge diversity of bioactive compounds, thousands have already been isolated, chemically characterized and shown to have biochemical targets e.g. particular proteins, notably receptors and specific enzymes (protein catalysts crucial for cellular function) [1]. The potential chemical complexity of potential use to Humanity is made even greater if such bioactive compounds are used as “lead compounds” for the chemical synthesis or derivatizing (semi-synthesis) to yield novel derivatives with useful pharmacological properties.

Thus, for example, according to WHO: “About 3.2 billion people – almost half of the world’s population – are at risk of malaria. In 2013, there were about 198 million malaria cases (with an uncertainty range of 124 million to 283 million) and an estimated 584 000 malaria deaths” [10]. The natural product artemisinin (quinghaosu) from the plant Artemisia annua (Asteraceae) is of major importance as an antimalarial drug and numerous artemisinin analogues with anti-malarial activity have now been synthesized and studied [11].

Conclusions.

Unique ecosystems and their constituent organisms must not be destroyed for 3 fundamental kinds of reasons:

(1) aesthetic reasons that we should not destroy unique ecosystems (ecocide) and the plant, animal, fungal, and bacterial species within them (speciescide) – civilized people cannot destroy what they cannot replace;

(2) utilitarian reasons based on the economic value of what remains of wild Nature [7] and particularly potential pharmacological resources within such ecosystems – thus thousands of chemical compounds have been isolated from plants and other organisms and shown to have specific biochemical targets with potential pharmaceutical applicability [1]; and

(3) intergenerational justice and intergenerational equity – we are destroying the irreplaceable biological complexity of the Earth and in doing so are robbing future generations of their birthright.

All civilized people – and especially young people [12-14] – must take action against the remorseless, neoliberal omnicide and terracide by (a) informing everyone they can and (b) applying Boycotts, Divestment and Sanctions (BDS) against all people, politicians, parties, companies, corporations and countries disproportionately involved in this terminal environmental vandalism. We are badly running out of time to stop this relentless, neoliberal terracide.

References.

[1]. Gideon Polya, “ Biochemical Targets of Plant Bioactive Compounds. A pharmacological reference guide to sites of action and biological effects”, Taylor and Francis and CRC Press, London and New York, 2004: http://www.crcpress.com/product/isbn/9780415308298 .

[2]. Kew Royal Botanic Gardens, “How many flowering plant species are there in the world?”: http://www.kew.org/science-conservation/plants-fungi/environment/how-many-flowering-plants-are-there-world .

[3]. Juliette Jowitt, “Scientists prune list of world’s plants”, Guardian, 20 September 2010: http://www.theguardian.com/science/2010/sep/19/scientists-prune-world-plant-list .

[4]. D.L. Hawksworth and A.Y. Rossman, A. Y. , “Where are all the undescribed fungi?” Phytopathology 87, 888-891, 1997: http://cals.arizona.edu/classes/plp427L/undescfungi.pdf .

[5]. Frederick M. Cohan, “Bacterial species and speciation”, Syst. Biol. 50(4):513–524, 2001: http://wesscholar.wesleyan.edu/cgi/viewcontent.cgi?article=1359&context=div3facpubs .

[6]. Phillip Levin, Donald Levin, “The real biodiversity crisis”, American Scientist, January-February 2002: http://www.americanscientist.org/issues/pub/the-real-biodiversity-crisis .

[7]. Gideon Polya, “International consensus-based IPCC Summary For Policymakers (2014) downplays acute seriousness of Climate Crisis”, Countercurrents, 12 November, 2014: http://www.countercurrents.org/polya121114.htm .

[8]. “Are we doomed?”: https://sites.google.com/site/300orgsite/are-we-doomed .

[9]. Andrew Balmford, “”, Science 9 August 2002, Economic Reasons for Conserving Wild Nature, Science Vol. 297, pp. 950 – 953: http://www.sciencemag.org/cgi/content/abstract/297/5583/950 .

[10]. WHO. Malaria”: http://www.who.int/features/factfiles/malaria/en/ .

[11]. Rafiee et al, “The role of charge distribution on the antimalarial activity of artemisinin derivatives”, Journal of Chemical Information and Modeling”: http://pubs.acs.org/doi/abs/10.1021/ci049812v .

[12]. “Climate Justice & Intergenerational Equity”: https://sites.google.com/site/300orgsite/climate-justice .

[13]. “Stop climate crime”: https://sites.google.com/site/300orgsite/stop-climate-crime .

[14]. Gideon Polya, “Letter To Young People Over $220 Trillion Carbon Debt: Revolt (Peacefully)”, Countercurrents, 11 July, 2014: http://www.countercurrents.org/polya110714.htm .